Modular Bag-N-Box Systems Patented QuadTruss® design (patent #5,390,803), making shelves up to 25% stronger and provides a retaining ledge for increased storage stability and product retention. Front 1Ë? ledge is provided on slanted shelf. Wire shelves constructed of chrome plated mild steel. 54Ë? posts have adjustable feet. Shelves adjustable on 1Ë? increments. All models are provided with a top